Method and apparatus for acoustical shielding

ABSTRACT

An open ended, generally U-shaped acoustical shield adapted for positionment with one open end thereof adjacent the body supporting surface of a bed to position the upstanding U-shaped shield in spaced, surrounding relation to the top and sides of the head of a recumbent.

United States Patent 1 1 3,780,825 Rinaldi 1451 Dec.25,1973

[ METHOD AND APPARATUS FOR ACOUSTICAL SHIELDING Inventor: Fred J. Rinaldi, 63 Wakelee Rd., Wolcott, Conn. 06716 Filed: on. 18, 1972 Appl. No.: 298,794

US. Cl 181/33 G, 181/33 GB, 181/33 GC, 5/67, 5/159 C, 5/329, 5/330 Int. Cl. E04b l/99, G10k 11/04 Field of Search .L 5/53 B, 52, 67, 69, 5/93 R, 101,159 C, 330, 327 B; 181/33 A,

33 G, 336 A, 336 B, 336 C, 33 OD References Cited UNITED STATES PATENTS 11/1964 Kerr 5/327 R FOREIGN PATENTS OR APPLICATIONS 1,466,371 12/1966 France 181/33 GC Primary Examiner-Richard B. Wilkinson Assistant Examiner-Vit W. Miska t ney: 91995? 519 9 [57] ABSTRACT An open ended, generally U-shaped acoustical shield adapted for positionment with one open end thereof adjacent the body supporting surface of a bed to position the upstanding U-shaped shield in spaced, surrounding relation to the top and sides of the head of a recumbent.

5 Claims, 6 Drawing Figures METHOD AND APPARATUS FOR ACOUSTICAL SHIELDING BACKGROUND OF THE INVENTION The invention relates to the acoustical shielding of recumbents and particularly hospital patients.

Ambient and background noise levels in hospitals normally exceed those to which the average patient is accustomed thus contributing to patient discomfort and increased recovery time both by reason of dis turbed rest and subjective aggravation. The presence of these noise levels is a necessary corollary of normal hospital activity and their abatement to any significent degree is inconsistent with established routines. Thus exemplary background noises, i.e. those not originating in the immediate vicinity of the patient, include call announcements for hospitalpersonnel over a public address system; the movement and operation of hospital equipment; normal cleaning and maintenance procedures; and, to a lesser degree, hospital personnel traffic and conversation. Ambient noises, which are normally even more distracting, derive from many of the foregoing causes as a patient or immediate neighbor in a ward or room is being monitored or attended. Although of limited duration; overall noise levels increase substantially during normal hospital visiting hours and ambient noises originating from conversations between adjacent patients and their visitors are particularly disruptive of sleep.

With the exception of visiting hour distractions most of the foregoing factors are present in all hospitals, at least to some extent, on a 24 hour basis as a necessary incident of normal hospital functions and routine. Stated differently, these noise levels are a fact of hospital life and the approach to patient relief must, there fore, be on some basis other than elimination of the sources. Although not readily susceptible of quantitative determination, the direct relationship between recovery time and undistracted patient rest is self evident with undisturbed sleep being generally acknowledged as a significent recovery factor for any convalescence.

While the foregoing relate to hospitalized patients in general, a more acute area of concern exists with respect to patients in intensive care units. Not only are these patients in greater need of rest but it is the very fact of the need for intensive care and the necessary grouping of intensive care patients that creates the necessity for increased equipment movement, personnel traffic and conversation immediately adjacent the patient and this condition, in intensive care units, is not abated during normal sleeping hours. g

In view of the foregoing, it is apparent that any practical approach to the problem of noise attenuation must involve an acoustical isolation of the patient with respect to the surrounding sources.

From an engineering standpoint, the solution to the problem would be absurdly simple involving nothing more than enclosing either the entire body or the head of a patient within an acoustical shield. Disclosures suggestive of this latter solution appear in French Pat. Nos. 1,459,167 and 1,466,371.

Although the use of body and/r head enclosing structure may or may not be practical for home and/or infant use they are, even apart from the normal claustrophobic tendencies that would be engendered by their use, totally unacceptable for hospital usage. This for the primary reason that at least the head of the patient must be exposed to attending personnel at all times whether for simple monitoring or to provide visual impressions of vital functions. Similarly, impairment of access to the patient such as by a required movement of bulky shielding in order to gain full access for treatment and/or equipment positionment precludes any possibility of hospital acceptance of any shielding equipment which inhibits full access to, or viewing of, the patient. Similar objections from the standpoint of patient acceptance include a tendency to create feelings of claustrophobia, decreased ventilation and an obvious desire on the part of the patient to be fully exposed for necessary monitoring and attendance.

It is the primary object of the invention to provide acoustical shielding for hospital patients which does not substantially impair a recumbents normal field of vision nor restrict visual monitoring of, and physical access to, the patient.

The shield design is, of course, a compromise to provide maximum shielding consistent with broad exposure of the patient for the resaons already enumerated and advantage is taken of the shielding and absorption of reflected sound patterns. Stated differently, that majority of direct and reflected sound wave propogation that would normally reach the ears of a patient along a path of travel outside the field of vision afforded by the shield are interrupted or shielded by the exterior shield wall while incoming sound patterns within the field of vision are partially attenuated by an inner shield wall of sound absorptive material.

SUMMARY OF THE INVENTION The foregoing is achieved .by the use of an open ended generally U-shaped acoustical shield which is positioned at the head end of a bed to encompass, in widely spaced relation, the top and sides of a patients head. Preferably the legs of the U-shaped shield which extend from thehead end of the bed toward the foot end of the bed are spaced apart a distance substantially equal to the width of the bed and extend vertically above the level of a recumbents head not more than approximately 2 feet. These approximating parameters have been found, in practice, not to engender feelings of claustrophobia, presumably because of the virtually unrestricted wide field of vision afforded the patient by such a construction. Thus with the patient lying on his back the field of vision both upwardly and toward the foot of the bed is totally unrestricted as is visual access to the patient from these positions which are the normal ones for attending personnel. Actually, with the shield structure of the inveniton the patient is totally exposed to the view of any person standing nearby. Similarly, physical access to the patient is readily available with the shield terminating at approximately shoulder level and ready access being had over the low shield wall to any portion of the upper torso or head.

The shield is mounted for movement between the operative position just described and one of two adjusted positions. The first of these adjusted positions permits the side walls of the U-shaped shield to be swung outwardly about an axis generally in the bight of the U while the second adjusted position permits entire shield removal from the vicinity of the patients head, either vertically or rearwardly.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan illustration of an acoustically shielded recumbent in accordance with a first embodiment of the invention;

FIG. 2 is a front perspective view of the shield and mounting structure shown in FIG. 1;

FIG. 3 is a cross-sectional view of the shield wall taken along line 33 of FIG. 2;

FIG. 4 is a rear perspective view of the shield and mounting structure of FIG. 2 illustrating one adjusted position of the shield;

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 4 illustrating the adjustment mechanism; and

FIG. 6 is a side elevation of a modified shield mounting structure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIGS. 2 and 4 is illustrated a floor supported embodiment of the invention wherein the generally U- shaped acoustical shield 10 is mounted on upright standard 12 for verticaland tilting adjustment in a vertical plane relative to weighted base 14 through the intermediary of conventional telescoping and tilt adjustment connections 16, 18. i

In a preferred embodiment of the invention; the shield 10 comprises symmetrical wing pairs 20, 22 which are mounted adjacent the upper end of standard 12 for limited relative pivotal movement in a horizontal plane between the maximum shielding and access positions illustrated by phantom and solid lines, respectively, in FIG. 4. The shielding wings 20, 22 are retained in the maximum shielding and access positions of FIG. 4 by spring loaded ball detents 24 (FIG. 5) which may be manually overridden, in conventional fashion, to adjust the same about the axis of standard 12.

The acoustical shield 10, being constructed to take advantage of the basic acoustic principles of shielding and absorption, comprises an inner sound absorption core 26 sandwiched between an outer support shield 28 and a perforated inner liner 30. Outer support shield 28 may comprise any of a variety of known acoustical shielding materials such as aluminum of fiber gkass, for example, and may, if desired, include a laminated construction such as lead lined aluminum sheet. The perforated inner liner 30 is preferably constructed from stainless steel sheet to enhance transmission to the sound absorption core 26 which may comprise polyurethane foam of fiber glass. A high porosity, disposable cover (not shown) may, if desired, be used to enclose the shield 10.

provided the same includes the necessary dimensions to extend, in widely spaced relation, about the top and along the sides of the head of a recumbent generally after the fashion illustrated in FIG. 1. The opposite open ends of the shield are preferably truncated and the upper end thereof, when viewed in the use position, includes an inturned flange 32. The truncated lower end is adapted to rest on the body supporting surface of a bed in bounding relation to the normal head and pillow supporting area while the inturned flange construction at the upper end is employed because it has been found that the presence of the flange 32 permits the height of the shield structure to be reduced while yet retaining the attenuation qualities of a shield having a greater vertical height; the reduction in height being desirable for the reason of increasing patient accessibility and decreasing the possibility of inducing claustrophobia.

Exemplary parameters for a shield construction which, in actual practice, produced a 20 db reduction in noise transmission from a typical hospital enviroment to a shielded recumbent included a shield height (measured along the longitudinal axis 34 of the shield) of 22 inches, an inturned flange width of 2 inches, a 31 inch spacing between'the inner surfaces of the outermost ends of the shield wings 20, 22 and a shield wing length (measured from the bight of the U to an imaginary line joining the outermost ends of the shield wings) of 27 inches.

In the use of the embodiment shown in FIGS. l-S; shield 10 is positioned in bounding relation to the top and sides of the head of a recumbent as illustrated in FIG. 1. It will be apparent that the recumbents field of vision, from a back rest position, is virtually, totally unrestricted and the widely spaced relation of the side wings would normally appear only in a peripheral field of vision so that there is, additionally, no feel of being enclosed. Similarly the patient is totally exposed from the foot end of the bed through the open end of the U-shaped shield which is the usual position for visual monitoring while the relatively low height extension of the shield renders the patients head readily available for physical access by a standing attendant even in the absence of a deliberate movement of the shield wings to the solid line access position of FIG. 4. Although the height of the shield structure may be varied with an obvious correlation between shield height and degree of sound attenuation, the approximate 2 foot shield height referred to herein represents an attractive compromise withregard to both shielding and patient accessibility.

Vertical adjustment via telescopic connection 16 is for the obvious purpose of accomodating variations in bed height or to permit removal of the shield, vertically, to a non-use position while the tilt adjustment connection 18 is to permit utilization of the shield when the body support surface of the bed is in a tilted or chaise lounge mode as illustrated in FIG. 6. When not in use, the shield 10 may be swung upwardly and rearwardly about adjustment connection l8'to clear the head end of the bed if space permits. When the head end of the bed is against a wall, removal is effected via vertical adjustment 16 as already explained.

The shield 10', shown in FIG. 6, is identical to that of FIGS. 1-5 but is supported on the bed frame 36 through a tilt adjustment connection 38. The use of the shield 10 is the same as that described in connection with the shield 10.

I claim:

1. Apparatus for acoustically shielding a recumbent, comprising; an open ended acoustical shield having generally U-shaped wall means extending at least about a longitudinal axis thereof; support means for supporting said acoustical shield adjacent the head supporting area of a recumbent support surface with the longitudinal axis thereof substantially perpendicular to the recumbent support surface to position the bight and one open end of the U-shaped wall means in engagement with the head end of the recumbent support surface and the open side of the U-shaped wall means opening toward the foot end of the support surface; and adjustment means mounting said acoustical shield on said support means for movement into and out of maximal shielding relation to the head supporting area of a recumbent support surface.

2. The apparatus of claim 1 wherein said adjustment means further includes means mounting said acoustical shield for movement of'the longitudinal axis thereof in a generally vertical plane.

3. The apparatus of claim 1 wherein said adjustment means further includes means mounting said wall means for movement transversely to said axis.

4. The apparatus of claim 1 wherein the other open end of said wall means terminates in an inturned flange.

5. In combination with body support means having a body support surface including a head supporting area, the improvement, comprising; a truncated, open ended, trough shaped acoustical shield having a longitudinal axis; and means supporting said acoustical shield for movement thereof between a first recumbent shielding position with the longitudinal axis thereof substantially perpendicular to the body support surface and one truncated end thereof in juxtaposition to said body support surface in at least semi-peripheral surrounding relation to said head supporting area and a second position spaced from said shielding position. 

1. Apparatus for acoustically shielding a recumbent, comprising; an open ended acoustical shield having generally U-shaped wall means extending at least 180* about a longitudinal axis thereof; support means for supporting said acoustical shield adjacent the head supporting area of a recumbent support surface with the longitudinal axis thereof substantially perpendicular to the recumbent support surface to position the bight and one open end of the U-shaped wall means in engagement with the head end of the recumbent support surface and the open side of the U-shaped wall means opening toward the foot end of the support surface; and adjustment means mounting said acoustical shield on said support means for movement into and out of maximal shielding relation to the head supporting area of a recumbent support surface.
 2. The apparatus of claim 1 wherein said adjustment means further includes means mounting said acoustical shield for movement of the longitudinal axis thereof in a generally vertical plane.
 3. The apparatus of claim 1 wherein said adjustment means further includes means mounting said wall means for movement transversely to said axis.
 4. The apparatus of claim 1 wherein the other open end of said wall means terminates in an inturned flange.
 5. In combination with body support means having a body support surface including a head supporting area, the improvement, comprising; a truncated, open ended, trough shaped acoustical shield having a longitudinal axis; and means supporting said acoustical shield for movement thereof between a first recumbent shielding position with the longitudinal axis thereof substantially perpendicular to the body support surface and one truncated end thereof in juxtaposition to said body support surface in at least semi-peripheral surrounding relation to said head supporting area and a second position spaced from said shielding position. 